MARINE RESERVE IMPLEMENTATION: CENTRAL FOREST BIOLOGICAL SURVEY OF THE MAJOR BENTHIC HABITATS OF THE GEOGRAPHE BAY-CAPES-HARDY INLET REGION (GEOGRAPHE BAY TO FLINDERS BAY) 28 JANUARY-8 FEBRUARY Summary Report: MRI/CF/GBC-27/1999 Prepared by G A Kendrick, A Brearley, J Prince, E Harvey, C Sim, K P Bancroft, J Huisman & L Stocker November 1999 Marine Conservation Branch Department of Conservation and Land Management 47 Henry Street Fremantle, Western Australia, 6160 Marine Conservation Branch CALM MARINE RESERVE IMPLEMENTATION: CENTRAL FOREST BIOLOGICAL SURVEY OF THE MAJOR BENTHIC HABITATS OF THE GEOGRAPHE BAY-CAPES-HARDY INLET REGION (GEOGRAPHE BAY TO FLINDERS BAY) 28 JANUARY-8 FEBRUARY 1999 Summary Report: MRI/CF/GBC-27/1999 A collaborative project between CALM’s Marine Conservation Branch and South West Capes District Office, and the University of Western Australia A project partially funded through the Natural Heritage Trust’s Coast and Clean Seas Marine Protected Area Programme Project No: WA9703 Prepared by Gary A. Kendrick, Anne Brearley, Jane Prince, Euan Harvey & Cameron Sim The University of Western Australia Kevin Bancroft Marine Conservation Branch, CALM John Huisman & Laura Stocker Murdoch University November 1999 Marine Conservation Branch Department of Conservation and Land Management 47 Henry St Fremantle, Western Australia, 6160 T:\REPORTS\MRI\mri_2799\mri_2799.doc 10:08 18/12/99 Marine Conservation Branch CALM T:\REPORTS\MRI\mri_2799\mri_2799.doc 10:08 18/12/99 Marine Conservation Branch CALM ACKNOWLEDGMENTS Direction · Dr Chris Simpson - Manager, Marine Conservation Branch (MCB), Nature Conservation Division. CALM Collaboration · Kevin Bancroft - Marine Conservation Officer, MCB. · Tim Daly – Marine Technical Officer, MCB. · Mike Lapwood - Marine Operations Officer, MCB. · Sue Elscot – Field Officer, MCB. · Roger Banks - Manager, South West Capes District · Charlie Broadbent - Senior Operations Officer, Southwest Capes District External Collaboration · Gary Kendrick - Project Leader, Botany Department, University of Western Australia. · Anne Brearley, Botany Department, University of Western Australia. · Euan Harvey, Botany Department, University of Western Australia. · Cameron Sim, Botany Department, University of Western Australia. · Matt Vanderklift, Botany Department, University of Western Australia. · Jane Prince, Zoology Department, University of Western Australia · John Huisman, School of Biological and Environmental Sciences, Murdoch University. · Laura Stocker, Institute for Science and Technology Policy, Murdoch University. · Mark Westera, Centre for Ecosystem Management, Edith Cowan University. · Eva Boogard, Professional underwater photographer. · Skipper and crew of the MV Voyager. Funding and resources The Geographe Bay-Capes biological survey is partially funded by a grant of $72,000 through the Natural Heritage Trust’s Coast and Clean Seas Marine Protected Area Program. Resources including scientific supervision, technical assistance, logistical support and instrumentation were provided by the MCB ($87,000). Cover. Cowaramup Bay (orthophotograph) This report may be cited as: Kendrick G.A., Brearley A., Prince J., Harvey E., Sim C., Bancroft K.P., Huisman J. & Stocker L. (1999). Biological survey of the major benthic habitats of the Geographe Bay-Capes-Hardy Inlet region (Geographe Bay to Flinders Bay) 28 January-8 February 1999. Summary Report: MRI/CF/GBC-25/1999. November 1999. Prepared by the Botany Department, University of Western Australia for the Marine Conservation Branch, Department of Conservation and Land Management, Fremantle, Western Australia. Copies of this report may be obtained from Marine Conservation Branch Department of Conservation and Land Management 47 Henry Street, Fremantle, Western Australia 6160 Ph: 61-8-9432 5102 Fax: 61-8-9430 5408 I T:\REPORTS\MRI\mri_2799\mri_2799.doc 10:08 18/12/99 Marine Conservation Branch CALM EXECUTIVE SUMMARY In January/February 1999, a biological survey was undertaken in the Geographe Bay-Capes-Hardy Inlet area. These areas were recommended by the Marine Parks and Reserves Selection Working Group (Marine Parks and Reserves Selection Working Group, 1994) for consideration as marine conservation reserves under the Conservation and Land Management (CALM) Act (1984). This survey was a collaboration between the Department of Conservation and Land Management and the University of Western Australia. The objectives of the survey were achieved and are as follows: · to develop a quantitative description of marine biota at representative sites within the major benthic habitats of the region; · to perform a quantitative analysis of species richness within the major benthic community types; · to investigate the influence of physical parameters, such as substrate type and wave exposure, on community diversity; · to acquire a collection of fauna and flora density and biomass data as baseline information for long-term monitoring of communities before and after marine reserve implementation, and; · the secondary objective of the survey was the opportunistic collection of qualitative information on visually dominant marine fauna and flora. Assemblages of marine algae in the study area were high in species diversity, with 154 species recorded from the survey. Many species were rarely sampled and were not recorded at many sites. Algal assemblages on granite reef and boulder fields have not previously been characterised in temperate Western Australia. There was a significant difference between the algal assemblages on deeper offshore granite reefs and shallow onshore reefs (both limestone and granite). Sponges and ascidians were diverse components of the sessile benthos. They were not sampled intensively in this survey, but show some patterns, suggesting that more research effort should be expended on these groups. Spatial patterns of fish abundance and size indicate that all sites are homogenous over the study area, however there is statistical difference in the fish community between inshore and offshore reefs. The fauna on the intertidal rock platform sampled in this survey had a low diversity and the spatial analysis demonstrated that the limestone platforms had a different faunal assemblage to that of the intertidal granitic boulder fields. Assemblages in the boulder fields were similar across the study area, however the assemblages on limestone platforms differed from the granitic boulder fields and from each other. The difference between the fauna of limestone and granitic areas can be explained by differences in their microtopography. Granites have relatively smooth surfaces in comparison to limestone areas, which have an irregular outline and surface. II T:\REPORTS\MRI\mri_2799\mri_2799.doc 10:08 18/12/99 Marine Conservation Branch CALM RECOMMENDATIONS SUBTIDAL Zoning Recommendation 1. Any zoning strategy for the proposed marine conservation reserve should replicate full and partial conservation zones in the northern, western and southern sections of the Recommendation 2. Distribution of marine algae was significantly influenced by m, 10-20 m) for regions. Recommendation 3. Algal assemblages on high relief reef were not significantly different from low relief reef, but this more likely reflects the sampling intensity of the survey. Including this stratum in a zoning strategy is recommended. Algae Recommendation 4. The stratified biodiversity survey design was able to differentiate clear differences between algal assemblages across geographical regions, reef type and water depth with a minimum number of sites and replicates within sites. Further use of this design is recommended. algal species, species distributions and species turnover suggest that marine algae in the study area are major components of the Algal assemblages should be a key component of further surveys. Ascidians Recommendation 6. Both sponges and ascidians were poorly studied during this survey, but show high diversity and high species turnover within and between sites. Both sponges and ascidians are candidates for future surveys. III T:\REPORTS\MRI\mri_2799\mri_2799.doc 10:08 18/12/99 Marine Conservation Branch CALM Fish Recommendation 7. There were more species of fish occurring in offshore versus onshore sites, however fish density seems to be more site specific. It is recommended that an offshore versus onshore stratum is included in the future zoning strategy. Recommendation 8. Both species richness and fish density were shown to have high levels of observer bias. Observer bias is generally larger than differences between sites. The non-destructive scuba visual survey methods seems inappropriate, and the effort expended (a team of five scuba divers) is not cost effective. We recommend that visual surveys of fish are not included in future biodiversity surveys. Recommendation 9. The use of remote video should be investigated and if necessary, developed to replace the present visual survey method. INTERTIDAL Zoning Recommendation 10. Limestone intertidal reefs areas of Yallingup, Kilcarnup and Prevelly are warranted special protection because of their accessibility and high diversity of species. Recommendation 11. Granitic boulder fields in sheltered habitats such as Cowaramup and Sugar Loaf should also be protected because of the high diversity of species found in the immediate subtidal. IV T:\REPORTS\MRI\mri_2799\mri_2799.doc 10:08 18/12/99 Marine Conservation Branch CALM TABLE OF CONTENTS ACKNOWLEDGMENTS................................................................................................................................I